From: Jacob Fugal <lukfugl@...>
Date: 2005-07-06T00:52:40+09:00
Subject: Re: Add methods to a predefined class: on the class instance or metaclass?

On 7/4/05, Robert Klemme <bob.news@gmx.net> wrote:
> 
> class Foo
>   def Foo.bar1() "bar1" end
> 
>   def self.bar2() "bar2" end
> 
>   class <<self
>     def bar3() "bar3" end
>   end
> 
>   class <<Foo
>     def bar4() "bar4" end
>   end
> end

Note that the last form (class << Foo) doesn't need to be inside the
reopened class:

  $ cat > a.rb
  class Foo; end

  class << Foo
    def test
      puts "Hello, world!"
    end
  end

  Foo.test

  $ ruby a.rb
  Hello, world!

Jacob Fugal